Explosive composition



Patented Nov. 27, 1945 PATENT OFFKCE EXPLOSIVE COMPOSITION Kenneth M. Gaver, Columbus, Ohio, assignor to The Komel Corporation, Dayton, Ohio, a corporation of Delaware No Drawing. Application February 15, 1941, Serial No. 379,128

' Claims.

This invention relates to explosives, and more particularly to an improved low density explosive comprising a starchate compound as an absorbent ingredient and modifying agent.

It is an object of this invention to provide an improved explosive which is less bulky than the conventional explosive compositions of this character and wherein the filler ingredient is an explosive compound,

Another object; is to provide an explosive product in which the absorbent ingredient is an amylaceous compound comprising a nitro or thio component.

Another object is to provide an explosive product wherein the porous absorbent material comprises an alkali metal or ammonium compound of starch which functions both as an absorbent for the liquid explosive ingredients, to provide a less sensitive product, and as an explosive constituent of the composition.

Still another object of this invention is to provide a pulverulent starch derivative substance as an absorbent or bulking material which can be readily mixed with liquid explosive ingredients such as in the preparation of dynamite and similar explosive products.

These and other objects and advantages will be apparent from the following description.

According to the present invention, I utilize a metallic starchate compound or starch derivative thereof as the absorbent or bulking ingredient in the compounding of explosive products. It has been proposed heretofore to use starch as a reaction product for preparing certain'explosive compositions, but the utilization of a starchate compound as an absorbent ingredient in the Preparation of explosives has not been practiced before my discovery. The particular starchate compound used may be selected to correspond to the metal salt which will provide the desired property to the explosive composition, and, in general, there may be employed the alkali metal starchates and ammonium, nitro or thio starchate compounds. In the use of the latter nitro and thio derivatives starch compounds, the ingredient functions not only as an absorbent but as an explosive substance in view of the presence of the nitrogen and sulphur elements.

The amount of the starchate compound incorporated in the preparation of the different explosive products may vary widely depending upon the composition of the product.

My starchate explosive modifying agent may be produced by reacting starch with alcohol soluble hydroxides, such as sodium, potassium. and the like, under conditions such that the metallic starch alcoholate is produced wherein the alkali 10 droxide or a hydroxide starch addition compound.

The alkali metal starchate or a derivative compound thereof, either of which may be used in compounding my improved explosive products, may be made by reacting 417 pounds of flake caustic soda or caustic potash in approximately 500 gallons of industrial ethyl alcohol. The mixture is allowed to stand to precipitate the carbonate impurities present which are removed by filtration.

Approximately 500 pounds of dry starch (i. e.

potato starch) is introduced into the alcoholic NaOH solution and the Whole mixture refluxed for two hours below 98 degrees 1. while being vigorously stirred. The product is then filtered and washed free of alkali with ethyl alcohol and the filter product consisting of sodium starchate is dried in a vacuum even under '78 degrees C. equipped with means for preventing entry of carbon dioxide and means for recovery of the alcohol. The dry sodium starchate product may then be ground and screened and is ready for use.

Further details regarding the manufacture and characteristics of the metal starchates herein mentioned and derivatives thereof are given in my copending application Serial No. 357,995, filed September 23, 1940.

The sodium starcha'te compound made as described is adapted to form a starting compound for synthesizing the nitro or thio derivative com- 40 pounds since the alkali metal starchate compound undergoes the Williamson ether reaction to form derivative products.

The ammonium or thio derivative of starch can be prepared by suitably reacting the sodium starchate compound suspended in ethyl alcohol or similar solvent with ammonium nitrate or sulfur chloride to form the corresponding starch derivative compound.

Where ammonium nitrate is used to leach the sodium starchate, ammonium starchate contain.

ing sod um nitrate is formed. This product is referred to as ammonium nitrate starchate in the examples.

The following typical examples will further illustrate my invention, but it is understood that my invention is not limited to the particular compositions as described herein but is applicable to the preparation of various other explosive com positions.

Example I ,Parts by weight Nitroglycerin 60-80 Ammonium starchate 10-25 Diatomaceous earth, chalk, or wood meal 10-20 Other starch derivative compounds may be used in place of ammonium, i. e., thiochlorostarchate, thio-ammonium starchate, ammonium-nitrate starchate, etc., or suitable mixtures of these starch compounds.

Example II Parts by weight Nitroglycerin 20-35 Guncotton (12.8% or above of N) 60-70 Ammonium starchate. 5-15 The above ingredients may be incorporated in acetone to form a blasting gelatin. Other starchate compounds may be substituted for ammonium starchate or admixed therewith as set out above in Example I.

Example III Parts by weight TNT (trinitrotoluene) -15 Ammonium nitrate 40-65 Sodium starchate 5-10 In place of the sodium starchate, ammonium nitrate-starchate or thio starchate may be used.

Example IV Parts by weight Nitroglycerin 10-15 Ammonium starchate, thio-chloro, thioammonium, or nitro starchate 50-60 Sodium nitrate 5-1'0 Thio-chloro starchate is that compound resulting from the interaction of sodium starchate and sulfur monochloride according to the reaction Na starchate+S2Clz SzCl starchate-i-NaCl Thio-ammonium starchate is that compound resulting from the interaction of thio-chloro starchate and ammonium hydroxide accordin to the reaction Ammonium nitrate-starchate is, in effect, a mixture of ammonium starchate, sodium nitrate and ammonium nitrate. When this mixture is freed of its sodium nitrate impurity, the resulting product is ammonium starchate.

Nitrc starchate is that compound resulting from the nitration of starch derivatives prepared from metallicstarchates. For example,

the benzyl derivative of sodium starchate may be nitrated using a sulfuric acid-nitric acid or a phosphoric acid-nitric acid nitrating mixture.

In the foregoing examples, it will be appreciated that other suitable starchate compounds or mixtures may be incorporated with different explosive ingredients to form the explosive product. The starchate absorbent compound combines the colloidal action of the starch molecule with the more reactive metal ion or ammonium ion so as to provide a very active colloidal ingredient which performs a dual function. The ammonium compounds have explosive properties similar to ammonium nitrate and with the use of these compounds inert fillers, such as chalk, diatomaceous earth, and the like, are not necessary and a more eflicient explosive composition is provided.

The different starchate compounds which are desired may be formed from the alkali metal starchate by reacting the same with the appropriate acid metal or ammonium compound so as to produce a substitution product. The reactions for making the appropriate starchate maybe carried out with the use of alcohol as a solvent for the reacting salts. Other suitable solvents may also be used. In some cases, the reactions for forming the desired starchate product can be performed 'utilizing water as the solvent, but where the finished product is to be used as a powder, the drying of the finished material becomes an important factor.

Further, my starchate absorbent compounds, it will be appreciated, may be used in connection with the preparation of explosives, such as dynamites, blasting gelatin, smokeless powder, and other explosive products in which liquid or powdered ingredients are used. Although tlie'invention is more particularly applicable to explosive compositions made using liquid constituents, it will be understood that my invention is not to be limited to this type of product. Among the various explosive substances in which my starchate absorbent material may be used are nitroglycerin, picric acid, TNT, guncotton, tetryl (tetranitromethylaniline) ammonium nitrate, dynamite, mercury fulminate, etc. The starchate compound may be incorporated in one or more of the above ingredients for forming the explosive product and providing the less bulky composition.

It will be understood that my invention is adapted for widely different embodiments and that it comprehends use either as an absorbent material or as an explosive ingredient in conjunction with other conventionally used absorbents. By the use of my alkali starchate compound, the evolving of gases, such as CO, is rerpressed due to the alkali content and a higher proportionate amount of explosive .ingredients can-be used, as well as a higher proportionate quantity of nitroglycerin, TNT, or the like.

It will be understood that the above description is merely illustrative of the use to which my invention can be put, and it is to be further understood that the process employed in preparing the starchate substance and its recovery may be varied substantially, as well as the type of exlplosive or other substance in which the starchate material may be incorporated or utilized.

Further, such modifications in the use and processing of the explosive products as necessitated under different conditions and uses are contemplated to be within the scope of this invention.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An explosive composition comprising nitroglycerin and an absorbent material for said nitroglycerin consisting of a metal starchate compound selected from the group consisting of alkali metal starchate and ammonium starchate in which the metal is attached through an oxygen atom to a carbon atom in the 2-position of the starch molecule.

2. An explosive composition including nitroglycerin, ammonium nitrate, and an absorbent for said nitroglycerin explosive ingredient comprising a metal starchate selected from the group consisting of alkali metal starchate and ammonium starchate in which the metal is attached through an oxygen atom to a carbon atom in the 2-positlon of the starch molecule.

3. An explosive composition including nitroglycerin, ammonium nitrate, and an absorbent for said nitroglycerin comprising a metal starchate selected from the group consisting of alkali metal starchate and ammonium starchate in which the. metal is attached through an oxygen atom to a carbon atom in the 2-position of the starch molecule admixed with an inert filler.

4. A low density explosive product comprising nitroglycerin and thio-ammonium starchate in which the szNHi-group is attached through an oxygen atom to a carbon atom in the 2-position of the starch molecule.

5. Anexplosive composition comprising nitroglycerin and an absorbent comprising an ammonium starchate-nitrate mixture, said mixture comprising ammonium nitrate, sodium nitrate, and ammonium starchate in which the ammonium radical is attached through an oxygen atom to the carbon atom of the 2-position of the starch molecule.

6. An explosive composition comprising a metal starchate selected from the group consisting of alkali metal starchate and ammonium starchate in which the metal is attached through an oxygen atom to a carbon atom in the 2-positlon of the starch molecule.

7. An explosive composition comprising an alkali metal starchate in which the alkali metal is attached through an oxygen atom to a carbon atom in the 2-position of the starch molecule.

8. An explosive composition comprising an ammonium starchate in which the ammonium radical is attached through an oxygen atom to a carbon atom in the 2-positlon of the starch molecule.

9. An explosive composition comprising a starchate of the formula:

wherein M is a cation selected from the group consisting of alkali metal and ammonium radical.

10. A solid explosive product of low density comprising a mixture of a liquid explosive material with an absorbent comprising a dry, powdered starchate of an ion selected from the group consisting of alkali metal and ammonium ions, said ion being attached through an oxygen atom to a carbon atom in the 2-position of the starch molecule.

KENNETH M. GAVER. 

